Insights into Sars-CoV-2 vaccination in patients with chronic plaque psoriasis on systemic treatments.

Dear Editor,

Two vaccines against COVID‐19 have recently been approved by the FDA and EMA: BNT162b2 (BioNTech, Mainz, Germany and Pfizer, Pfizer Inc., New York, NY, USA) and mRNA‐1273 (Moderna, Cambridge, MA, USA). Both vaccines utilize mRNA that enters the patient cell and uses host protein transcription pathways to express viral spike proteins which then stimulate a specific antibody and T‐cell‐mediated immune response. They are both administered in two intramuscular doses: 3 weeks apart for BNT162b2, 4 weeks apart for mRNA‐1273. Phase 3 trials showed high efficacy rate in protection against COVID‐19 , (95% for BNT162b2 and 94.1% for mRNA‐1273) and no major safety concerns, with the most common adverse effects being injection site pain, headache, fever, fatigue, chills and myalgia. , As patients on immunosuppressive therapy were excluded from clinical trials, there are currently no data on the efficacy and safety of COVID‐19 vaccines in those treated with conventional or biologic disease‐modifying antirheumatic drugs (DMARDs). However, the COVID‐19 vaccine will soon be available also for patients with psoriasis receiving systemic treatments and some considerations are needed in this regard. In terms of safety, both BNT162b2 and mRNA‐1273 are expected to be safe in psoriatic patients on immunosuppressants given that they are not live vaccines as recently advised by the EADV Task Forces statements on COVID‐19 Vaccination. On the other hand, immunosuppressant treatment may theoretically reduce to some extent the efficacy of COVID‐19 vaccines. Conventional and biologic DMARDs have diverse mechanisms of action, which account for their different degree of immunosuppression and/or immunomodulating properties, so that some agents may impair the build‐up of an immune response against COVID‐19 vaccine more than others. For example, the IL‐17A inhibitor secukinumab was proved not to affect the humoral response to influenza vaccine of patients with psoriatic arthritis; similarly, ixekizumab was shown not to suppress humoral immune response to tetanus and pneumococcal vaccination. In a meta‐analysis comparing the humoral response to influenza and pneumococcal vaccination in adult patients with rheumatoid arthritis, it was found that methotrexate but not TNF‐α inhibitors exposure was associated with reduced 6B and 23F serotype pneumococcal vaccine response. Another important issue is whether psoriatic patients should discontinue their immunosuppressive treatment before and after receiving the vaccine to optimize the efficacy of the vaccination. Of note, since Pfizer‐BioNTech and Moderna vaccines are administered 3 and 4 weeks apart, respectively, the drug would need to be discontinued for several weeks and there would be a reasonable risk of psoriasis recurrence, also considering that the vaccination itself stimulate an IFN‐γ and TNF‐α release from Th1 cells. Ultimately, the durability of the protection against SARS‐CoV‐2 following vaccination has not been fully elucidated.

In conclusion, weighing the potential benefits and risks, we suggest providing SARS‐CoV‐2 vaccination for all psoriatic patients on immunosuppressant drugs, because, although they might show to be not as effective as in healthy subjects, they may still provide some degree of protection against COVID‐19. In the current and dramatic pandemic, some degree of immunity is better than no degree of immunity at all. Psoriatic patients receiving COVID‐19 vaccine and those who had COVID‐19 infection should also be advised to continue to follow all current guidance to protect themselves and others, as recently recommended by the EADV task force on quality of life and patient‐oriented outcome.

Since there are case reports of immunosuppressed patients (but also immunocompetent individuals) developing COVID‐19 reinfection, also psoriatic patients who already had COVID‐19 infection should be considered for the vaccination.

Registries enrolling dermatological patients undergoing SARS‐CoV‐2 vaccination and proactive pharmacovigilance activities especially focusing on patients under immunosuppressants are urgently needed to guide clinical practice.

Funding sources

Fondazione Cariplo, Fondazione Veronesi, Impact of COVID19 infection on patients affected by inflammatory skin diseases on immuno‐suppressive therapies (COVISKIN); ID 1833073 rif. 2020‐1363.